Radio access system and radio network evolution in cellular mobile communication (hereinafter referred to as “long term evolution (LTE)” or “evolved universal terrestrial radio access (EUTRA)”) is considered in the 3rd Generation Partnership Project (3GPP), and LTE-Advanced (also referred to as LTE-A or “Advanced EUTRA)”), which is a developed version to adopt a new technique, is also considered.
In Advanced EUTRA, in order to reduce or suppress interference with a mobile station apparatus or in order to increase received signal power, intercell coordinated (cooperative multipoint (CoMP)) communication to carry out communication between adjacent cells in coordination with each other, is considered. For example, a method for transmitting signals, subjected to different weighting signal processes (precoding processes) in a plurality of cells, to a signal mobile station apparatus in coordination with each other by a plurality of base station apparatuses (also referred to as joint processing (JP) or joint transmission (JT)), a method for scheduling a mobile station apparatus through coordination among a plurality of cells (coordinated scheduling (CS)), a method for transmitting a signal to a mobile station apparatus using beamforming through coordination among a plurality of cells (coordinated beamforming (CB)), and a method for transmitting a signal using a predetermined resource only by one cell and not transmitting a signal using a resource overlapping the resource by another cell (blanking or muting) are considered as examples of the intercell coordinated communication.
Note that a plurality of cells used for intercell coordinated communication may be cells managed by different base station apparatuses or may be cells managed by a single base station apparatus. Each cell may be composed of a radio unit (also referred to as a remote radio head (RRH) or a remote radio unit (RRU)) controlled by a control unit of a base station apparatus main body. The radio unit may be connected to the base station apparatus main body with a wire, such as an optical fiber, or may be connected wirelessly, as in a relay station apparatus.